A severe yellow warning for wind is in place until late on Wednesday night – bringing the risk of damage to buildings, fallen trees, road closures and large waves in coastal areas.
A strong jet stream out of Canada is responsible for the current spell of unsettled weather – which is expected to stay over the UK until Tuesday next week, the Met Office said.
Here are details of Storm Ali’s trail of destruction across Ireland and some parts of the UK so far.
:: One woman, reportedly a Swiss tourist in her 50s, has died after her caravan was blown off a cliff in west Ireland.
:: One man in his 20s has been killed and another in his 40s was injured after a tree fell on them in County Armagh as Ali battered Northern Ireland.
:: Around 75 flights have been cancelled and 10 flights diverted from Dublin Airport due to strong winds from Ali.
:: Scottish Power said 16,000 homes, most in central and southern Scotland, are without power. They have restored around 4,000 homes since 20,000 customers’ power was wiped out at 10am.
:: ESB Network said 186,000 customers across Ireland are without power – with fallen trees on overhead lines responsible for most of the damage to the network.
:: Electricity has been restored to over 55,000 customers across Northern Ireland following Ali’s severe gales. Approximately 41,000 homes and businesses remain without power.
:: The Met Office said gusts of 91mph hit Killowen in Country Down.
:: 77mph winds were recorded in Kirkcudbrightshire in Scotland.
:: 74mph gusts hit Capel Curig in Wales and 68mph was recorded in St Bees Head, Cumbria.
:: Wind gust speeds of 102.2mph were recorded on the Tay Road Bridge in Scotland – which has been shut to all traffic.
In further disruptions, authorities in Dumfries and Galloway said they are struggling to cope with the number of trees which have been blown into roads.
A section of Princes Street in Edinburgh has been closed after parts of a shop roof flew off in strong winds.
Police Scotland was alerted to lead falling from the Topshop building at around 12.30pm on Wednesday.
Rail companies have urged customers not to travel, with ScotRail tweeting it is dealing with “severe disruption” across Scotland.
There are also severe train delays across Ireland due to line closures and debris on the line.
Sky News’ weather producer Joanna Robinson said Ali will continue to bring “damaging gusts of up to 80 miles an hour” across central, southern and eastern Scotland.
“As Storm Ali moves away this evening and overnight, the winds will ease across all areas, but it will stay windy in the north,” she said.
“Thursday will see heavy rain moving north-eastwards, bringing the risk of flooding across Wales and northwest England.”
Further unsettled spells could see winds strengthening again on Thursday night, with southern parts being affected.